Friction stir additive manufacturing systems and methods

ABSTRACT

A method of depositing an extrudate onto a substrate, the method including steps of rotating a stirring tool about an axis of rotation while urging a tool distal end of the stirring tool against the substrate, and wherein the stirring tool defines a bore, extending therethrough; positioning a die adjacent to the stirring tool, such that the stirring tool rotates relative to the die; and passing feedstock through the bore toward the tool distal end.

PRIORITY

This application is a divisional of U.S. Ser. No. 16/220,346 filed onDec. 14, 2018.

TECHNICAL FIELD

The present disclosure generally relates to additive manufacturing and,more particularly, to additive manufacturing systems and methods fordepositing an extrudate onto a substrate using friction stir deposition.

BACKGROUND

Objects, made using additive manufacturing techniques, are fabricated byadding material layer by layer. Friction stir additive manufacturing isa solid-state additive manufacturing technique based on friction stirwelding. Additive friction stir deposition is a solid-state additivemanufacturing technique that combines friction stir welding with amaterial feeding and deposition process. In additive friction stirdeposition, feed material is delivered through a hollow friction stirtool. The friction stir tool rapidly rotates and generates heat throughdynamic contact friction at a tool-material interface. Heat is generatedby dynamic contact friction between the friction stir tool and amaterial, dissipated by plastic deformation of the material, andtransferred inside the material by thermal conduction. Heated andsoftened, the feed material is fed through the friction stir tool andbonds with a substrate through plastic deformation at the interface.However, an uncontrolled flow of material, radiating outward from thedeposition interface, may result in formation of areas having undesired,excess material. Formation of such excess material may lead tounfinished (e.g., rough or low quality) surface characteristics,inaccurate surface geometries, dimensions that are beyond acceptabletolerances, and/or other defects. Certain defects may requirepost-processing operations, which increase production cost. Certainother defects may require the object to be discarded, which increaseswaste. Accordingly, systems and methods, intended to address theabove-identified concerns, would find utility.

SUMMARY

Accordingly, apparatuses and methods, intended to address at least theabove-identified concerns, would find utility.

The following is a non-exhaustive list of examples, which may or may notbe claimed, of the subject matter, disclosed herein.

One example of the subject matter, disclosed herein, relates to anadditive manufacturing system for depositing an extrudate onto asubstrate. The additive manufacturing system comprises a depositionhead. The deposition head comprises a stirring tool, rotatable about anaxis of rotation A_(R) and comprising a tool distal end and a toolproximal end, axially opposing the tool distal end along the axis ofrotation A_(R). The stirring tool defines a bore, extending from thetool proximal end to the tool distal end. The bore is configured toreceive feedstock. The feedstock is biased toward the tool distal end.The deposition head also comprises a die. The die is positioned adjacentto the stirring tool. The die defines a die axis A_(D1). The diecomprises a die distal end and a die proximal end, axially opposing thedie distal end along the die axis A_(D1). The die axis A_(D1) isparallel with the axis of rotation A_(R) of the stirring tool.

The additive manufacturing system provides a wide range of capabilities,including additive manufacturing, coating applications, componentrepair, metal joining, and custom metal alloy and metal matrix compositebillet and part fabrication by depositing the extrudate onto thesubstrate. The die serves as a forming tool for controlling geometryand/or dimensions of the extrudate when deposited onto the substrate.

Another example of the subject matter, disclosed herein, relates to amethod of depositing an extrudate onto a substrate. The method comprisesrotating a stirring tool about an axis of rotation A_(R) while urging atool distal end of the stirring tool against the substrate. The stirringtool defines a bore, extending therethrough. The method furthercomprises positioning a die adjacent to the stirring tool, such that thestirring tool rotates relative to the die, and passing feedstock throughthe bore toward the tool distal end.

The method facilitates depositing layers of the extrudate onto thesubstrate to form a three-dimensional object. The die provides at leastone of a flow-inhibiting function and a surface-forming function forcontrolling geometry and/or dimensions of a side, or a surface, of theextrudate when depositing the extrudate onto the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

Having thus described one or more examples of the present disclosure ingeneral terms, reference will now be made to the accompanying drawings,which are not necessarily drawn to scale, and wherein like referencecharacters designate the same or similar parts throughout the severalviews, and wherein:

FIG. 1, is a block diagram of an additive manufacturing system fordepositing an extrude onto a substrate, according to one or moreexamples of the present disclosure;

FIG. 2 is a schematic, perspective view of a sub-assembly of theadditive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 3 is a schematic, perspective view of a sub-assembly of theadditive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 4 is a schematic, elevation, sectional view of a sub-assembly ofthe additive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 5 is a schematic, elevation, sectional view of a sub-assembly ofthe additive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 6 is a schematic, perspective view of a sub-assembly of theadditive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 7 is a schematic, perspective view of a die of the additivemanufacturing system of FIG. 1, according to one or more examples of thepresent disclosure;

FIG. 8 is a schematic, perspective view of a die of the additivemanufacturing system of FIG. 1, according to one or more examples of thepresent disclosure;

FIG. 9 is a schematic, elevation, sectional view of a sub-assembly ofthe additive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 10 is a schematic, elevation, sectional view of a sub-assembly ofthe additive manufacturing system of FIG. 1, according to one or moreexamples of the present disclosure;

FIG. 11 is a schematic, plan view of a deposition head of the additivemanufacturing system of FIG. 1, according to one or more examples of thepresent disclosure;

FIG. 12, is a block diagram of a method of depositing an extrude onto asubstrate utilizing the additive manufacturing system of FIG. 1,according to one or more examples of the present disclosure;

FIG. 13 is a block diagram of aircraft production and servicemethodology; and

FIG. 14 is a schematic illustration of an aircraft.

DETAILED DESCRIPTION

In FIG. 1, referred to above, solid lines, if any, connecting variouselements and/or components may represent mechanical, electrical, fluid,optical, electromagnetic and other couplings and/or combinationsthereof. As used herein, “coupled” means associated directly as well asindirectly. For example, a member A may be directly associated with amember B, or may be indirectly associated therewith, e.g., via anothermember C. It will be understood that not all relationships among thevarious disclosed elements are necessarily represented. Accordingly,couplings other than those depicted in the block diagrams may alsoexist. Dashed lines, if any, connecting blocks designating the variouselements and/or components represent couplings similar in function andpurpose to those represented by solid lines; however, couplingsrepresented by the dashed lines may either be selectively provided ormay relate to alternative examples of the present disclosure. Likewise,elements and/or components, if any, represented with dashed lines,indicate alternative examples of the present disclosure. One or moreelements shown in solid and/or dashed lines may be omitted from aparticular example without departing from the scope of the presentdisclosure. Environmental elements, if any, are represented with dottedlines. Virtual (imaginary) elements may also be shown for clarity. Thoseskilled in the art will appreciate that some of the features illustratedin FIG. 1 may be combined in various ways without the need to includeother features described in FIG. 1, other drawing figures, and/or theaccompanying disclosure, even though such combination or combinationsare not explicitly illustrated herein. Similarly, additional featuresnot limited to the examples presented, may be combined with some or allof the features shown and described herein.

In FIGS. 12 and 13, referred to above, the blocks may representoperations and/or portions thereof and lines connecting the variousblocks do not imply any particular order or dependency of the operationsor portions thereof. Blocks represented by dashed lines indicatealternative operations and/or portions thereof. Dashed lines, if any,connecting the various blocks represent alternative dependencies of theoperations or portions thereof. It will be understood that not alldependencies among the various disclosed operations are necessarilyrepresented. FIGS. 12 and 13 and the accompanying disclosure describingthe operations of the method(s) set forth herein should not beinterpreted as necessarily determining a sequence in which theoperations are to be performed. Rather, although one illustrative orderis indicated, it is to be understood that the sequence of the operationsmay be modified when appropriate. Accordingly, certain operations may beperformed in a different order or simultaneously. Additionally, thoseskilled in the art will appreciate that not all operations describedneed be performed.

In the following description, numerous specific details are set forth toprovide a thorough understanding of the disclosed concepts, which may bepracticed without some or all of these particulars. In other instances,details of known devices and/or processes have been omitted to avoidunnecessarily obscuring the disclosure. While some concepts will bedescribed in conjunction with specific examples, it will be understoodthat these examples are not intended to be limiting.

Unless otherwise indicated, the terms “first,” “second,” etc. are usedherein merely as labels, and are not intended to impose ordinal,positional, or hierarchical requirements on the items to which theseterms refer. Moreover, reference to, e.g., a “second” item does notrequire or preclude the existence of, e.g., a “first” or lower-numbereditem, and/or, e.g., a “third” or higher-numbered item.

Reference herein to “one example” means that one or more feature,structure, or characteristic described in connection with the example isincluded in at least one implementation. The phrase “one example” invarious places in the specification may or may not be referring to thesame example.

As used herein, a system, apparatus, structure, article, element,component, or hardware “configured to” perform a specified function isindeed capable of performing the specified function without anyalteration, rather than merely having potential to perform the specifiedfunction after further modification. In other words, the system,apparatus, structure, article, element, component, or hardware“configured to” perform a specified function is specifically selected,created, implemented, utilized, programmed, and/or designed for thepurpose of performing the specified function. As used herein,“configured to” denotes existing characteristics of a system, apparatus,structure, article, element, component, or hardware which enable thesystem, apparatus, structure, article, element, component, or hardwareto perform the specified function without further modification. Forpurposes of this disclosure, a system, apparatus, structure, article,element, component, or hardware described as being “configured to”perform a particular function may additionally or alternatively bedescribed as being “adapted to” and/or as being “operative to” performthat function.

Illustrative, non-exhaustive examples, which may or may not be claimed,of the subject matter according to the present disclosure are providedbelow.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 2-11,additive manufacturing system 110 for depositing extrudate 112 ontosubstrate 114 is disclosed. Additive manufacturing system 110 comprisesdeposition head 116. Deposition head 116 comprises stirring tool 118.Stirring tool 118 is rotatable about axis of rotation A_(R). Stirringtool 118 comprises tool distal end 120 and tool proximal end 122,axially opposing tool distal end 120 along axis of rotation A_(R).Stirring tool 118 defines bore 124. Bore 124 extends from tool proximalend 122 to tool distal end 120. Bore 124 is configured to receivefeedstock 126. Feedstock 126 is biased toward tool distal end 120.Deposition head 116 also comprises die 128. Die 128 is positionedadjacent to stirring tool 118. Die 128 defines die axis A_(D1). Die 128comprises die distal end 130 and die proximal end 132, axially opposingdie distal end 130 along die axis A_(D1). Die axis A_(D1) is parallel toaxis of rotation A_(R) of stirring tool 118. The preceding subjectmatter of this paragraph characterizes example 1 of the presentdisclosure.

Additive manufacturing system 110 provides a wide range of capabilities,including additive manufacturing, coating applications, componentrepair, metal joining, and custom metal alloy and metal matrix compositebillet and part fabrication by depositing extrudate 112 onto substrate114. Die 128 serves as a forming tool for controlling geometry and/ordimensions of extrudate 112 when deposited on substrate 114.

Additive manufacturing system 110 is a solid-state process; meaningfeedstock 126 does not reach melting temperature during the depositionprocess. In the additive friction stir deposition process using additivemanufacturing system 110, feedstock 126 is delivered through bore 124 ofstirring tool 118. Stirring tool 118 rapidly rotates and generates heatthrough dynamic contact friction at a tool-material interface. Heat isgenerated by dynamic contact friction between stirring tool 118 andbuild material. For the purpose of the present disclosure, the term“build material” refers to at least one of feedstock 126, extrudate 112,substrate 114, or some combination thereof. Heat is dissipated byplastic deformation of the build material. Heat is transferred insidethe build material by thermal conduction and thermal convection viamaterial flow. Heated and softened, feedstock 126 is fed throughstirring tool 118 as extrudate 112 and bonds with substrate 114 throughplastic deformation at the interface.

As illustrated in FIGS. 2, 3, and 6, transverse motion of stirring tool118, for example, in the direction of directional arrow 200, results indeposition of a single track, or a single layer, of extrudate 112. Asbest illustrated in FIGS. 4, 5, 9, and 10, a three-dimensional object ismade by selectively adding subsequent layers of extrudate 112 uponpreceding layers of extrudate 112 (e.g., three layers of extrudate 112are depicted in FIGS. 4, 5, 9, and 10).

In one or more examples, tool distal end 120 of stirring tool 118includes, or forms, a tool shoulder that is positioned in physical(e.g., direct) contact with a surface of substrate 114 (e.g., duringdeposition of an initial layer of extrudate 112) or a surface of apreceding layer of extrudate 112 (e.g., during deposition of asubsequent layer of extrudate 112). Bore 124 extends through the toolshoulder formed at tool distal end 120 of stirring tool 118 andfeedstock 126 is biased toward tool distal end 120 and is positioned inphysical (e.g., direct) contact with the surface of substrate 114 (e.g.,during deposition of an initial layer of extrudate 112) or a surface ofa preceding layer of extrudate 112 (e.g., during deposition of asubsequent layer of extrudate 112). Dynamic contact friction between thetool shoulder formed at tool distal end 120 of stirring tool 118 and thesurface of substrate 114 or the surface of a preceding layer ofextrudate 112 generate heat during rotation of stirring tool 118.Dynamic contact friction between a distal end of feedstock 126 and thesurface of substrate 114 or the surface of a preceding layer ofextrudate 112 generate heat during rotation of feedstock 126, which isco-rotated by rotation of stirring tool 118.

In one or more examples, surface quality of at least one layer of, oreach layer of, extrudate 112 and, thus, surface quality of at least aportion of the three-dimensional object, or the three-dimensional objectas a whole, is improved by use of die 128. As illustrated in FIGS. 2-5and 8-10, in one or more examples, die 128 is located, or is positioned,adjacent to stirring tool 118 during deposition of extrudate 112. Asused herein, the term “adjacent” means being near or in relatively closeproximity. It should be appreciated that the location of die 128relative to stirring tool 118 (e.g., the degree of proximity of die 128relative to stirring tool 118) depends on various factors, including,but not limited to, the desired (e.g., lateral) dimension of the layerof extrudate 112 being deposited along any given run of deposition head116 or the desired (e.g., lateral) dimensions of the three-dimensionalobject.

Further, for the purpose of the present disclosure, the term “parallel,”such as in reference to die axis A_(D1) of die 128 being parallel toaxis of rotation A_(R) of stirring tool 118, means that items are sideby side and have the same distance continuously between them. As usedherein, the term “parallel” includes a condition in which items areexactly parallel and a condition in which items are approximatelyparallel. As used herein, the term “approximately” refers to a conditionthat is close to, but not exactly, the stated condition that stillperforms the desired function or achieves the desired result, such as acondition that is within an acceptable predetermined tolerance oraccuracy. For example, the term “approximately” refers to a conditionthat is within 10% of the stated condition. However, the term“approximately” does not exclude a condition that is exactly the statedcondition.

In one or more examples, die axis A_(D1) of die 128 and axis of rotationA_(R) of stirring tool 118 are parallel to each other and reside in thesame virtual plane. In one or more examples, die axis A_(D1) of die 128resides in a virtual die-plane and axis of rotation A_(R) of stirringtool 118 resides in a virtual tool-plane, and the virtual die-plane andthe virtual tool-plane are parallel to each other.

Generally, during the deposition process, a portion of plasticized buildmaterial (e.g., softened portions of a current layer of extrudate 112being deposited and a previous layer of extrudate 112, on which thecurrent layer of extrudate 112 is deposited, or substrate 114 on whichthe current layer of extrudate 112 is deposited) may flow radiallyoutward from a deposition interface (e.g., the interface betweenstirring tool 118 and the build material). Die 128 is suitably locatedrelative to stirring tool 118, or relative to the deposition interfacebetween stirring tool 118 and the build material, so that die 128controls a material flow of plasticized build material that radiatesoutward from the deposition interface. In other words, die 128 serves asa physical stop for a radial flow of plasticized build material.

In one or more examples, die 128 enables dimensional control of thethree-dimensional object built during the deposition process usingadditive manufacturing system 110. Control of material flow using die128 enables control of at least one dimension (e.g., a lateraldimension) of each layer of extrudate 112 being deposited. In otherwords, die 128 prevents extrudate 112 from extending beyond a desireddimension and inhibits a build-up of excess material along a periphery(e.g., an external boundary of a surface) of the layer of extrudate 112being deposited.

Further, in one or more examples, die 128 enables control of a contourand/or control of surface characteristics of the periphery (e.g., sidesurface) of the layer of extrudate 112 being deposited. In one or moreexamples, die 128 provides for a planar or contoured side surface of thelayer of extrudate 112 being deposited. In one or more examples, die 128provides for a relatively smooth side surface of the layer of extrudate112 being deposited.

As illustrated in FIG. 2, in one or more examples, die 128 is used whenonly one surface, or only one side, of the layer of extrudate 112 beingdeposited needs to be controlled. For example, die 128 controls the flowof plasticized material at one location to prevent extrudate 112 fromextending beyond a predetermined limit at one side of the layer ofextrudate 112 being deposited and control of surface characteristics ofone side of the layer of extrudate 112 being deposited.

In one or more examples, die 128 and stirring tool 118 move togetherwhen depositing a layer of extrudate 112, for example, by transversemovement of deposition head 116. In one or more examples, die 128 andstirring tool 118 move independently. In such examples, die 128 movesinto position, followed by transverse movement of stirring tool 118 todeposit the layer of extrudate 112.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 2, 3, and5, stirring tool 118 is rotatable relative to die 128 about axis ofrotation A_(R). The preceding subject matter of this paragraphcharacterizes example 2 of the present disclosure, wherein example 2also includes the subject matter according to example 1, above.

Rotation of stirring tool 118 about axis of rotation A_(R) relative todie 128 enables independent rotational motion control of stirring tool118 relative to die 128.

As illustrated in FIGS. 2, 3, and 5, in one or more examples, stirringtool 118 rotates about axis of rotation A_(R) relative to die 128, forexample, in the direction of directional arrow 202. Stirring tool 118rotates in a clockwise direction or a counter clockwise direction, inone or more examples. Rapid rotation of stirring tool 118 generates heatthrough dynamic contact friction between stirring tool 118 and substrate114 (e.g., during deposition of an initial layer of extrudate 112) orbetween stirring tool 118 and a preceding layer of extrudate 112 (e.g.,during deposition of a subsequent layer of extrudate 112).

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 2-6, 9,and 10, stirring tool 118 comprises outer surface 134. Shortest distance136 between die 128 and outer surface 134 is at most 3 millimeters. Thepreceding subject matter of this paragraph characterizes example 3 ofthe present disclosure, wherein example 3 also includes the subjectmatter according to example 1 or 2, above.

Shortest distance 136 between die 128 and outer surface 134 of stirringtool 118, being at most 3 millimeters, limits a distance thatplasticized build material can flow radially outward from the interfacewith stirring tool 118 during deposition of any layer of extrudate 112and, thus, controls a dimension (e.g., a lateral dimension) of the layerof extrudate 112 being deposited.

In one or more examples, the term “3 millimeters” refers toapproximately 3 millimeters.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 2-6, 9,and 10, stirring tool 118 comprises outer surface 134. Shortest distance136 between die 128 and outer surface 134 is at most 1 millimeter. Thepreceding subject matter of this paragraph characterizes example 4 ofthe present disclosure, wherein example 4 also includes the subjectmatter according to example 1 or 2, above.

Shortest distance 136 between die 128 and outer surface 134 of stirringtool 118, being at most 1 millimeter, limits a distance that plasticizedbuild material can flow radially outward from the interface withstirring tool 118 during deposition of any layer of extrudate 112 and,thus, controls a dimension (e.g., a lateral dimension) of the layer ofextrudate 112 being deposited.

In one or more examples, the term “1 millimeter” refers to approximately1 millimeter.

In one or more examples, shortest distance 136 between die 128 and outersurface 134 of stirring tool 118 is less than 1 millimeter. In one ormore examples, shortest distance 136 between die 128 and outer surface134 is close to zero. In one or more examples, shortest distance 136between die 128 and outer surface 134 of stirring tool 118 is greaterthan 3 millimeters. It should be appreciated that shortest distance 136between die 128 and outer surface 134 of stirring tool 118 depends onvarious factors, including, but not limited to, the desired (e.g.,lateral) dimension of the layer of extrudate 112 being deposited alongany given run of deposition head 116 or the desired (e.g., lateral)dimensions of the three-dimensional object.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 2-6 and9-11, feedstock 126 is received in bore 124 such that rotation ofstirring tool 118 causes corresponding rotation of feedstock 126. Thepreceding subject matter of this paragraph characterizes example 5 ofthe present disclosure, wherein example 5 also includes the subjectmatter according to any one of examples 1 to 4, above.

Rotation of stirring tool 118 also rotates (e.g., co-rotates) feedstock126, located in bore 24 of stirring tool 118, about axis of rotationA_(R) relative to die 128. Rapid rotation of feedstock 126 generatesheat through dynamic contact friction between feedstock 126 andsubstrate 114 (e.g., during deposition of an initial layer of extrudate112) or between feedstock 126 and a preceding layer of extrudate 112(e.g., during deposition of a subsequent layer of extrudate 112).

As illustrated in FIG. 11, in one or more examples, feedstock 126 andbore 124 of stirring tool 118 have complementary cross-sectionalgeometries, viewed along axis of rotation A_(R) of stirring tool 118(FIGS. 2-6, 9, and 10). As such, a rotational orientation of feedstock126 is fixed relative to stirring tool 118, feedstock 126 is inhibitedfrom rotating relative to stirring tool 118, and feedstock 126co-rotates with stirring tool 118. As illustrated in FIG. 11, in one ormore examples, feedstock 126 and bore 124 of stirring tool 118 havecomplementary hexagonal cross-sections, viewed along axis of rotationA_(R) of stirring tool 118. In one or more examples, feedstock 126 andbore 124 of stirring tool 118 have any one of various othercomplementary cross-sections, viewed along axis of rotation A_(R) ofstirring tool 118, such as triangular, square, octagonal, and the like.

In one or more examples, feedstock 126 is biased toward tool distal end120 of stirring tool 118 and into contact with substrate 114 (e.g.,during deposition of an initial layer of extrudate 112) or a precedinglayer of extrudate 112 (e.g., during deposition of a subsequent layer ofextrudate 112) by a feed-stock force sufficient to inhibit rotation offeedstock 126 relative to stirring tool 118.

Referring generally to FIG. 1, feedstock 126 comprises metal or metalalloy. The preceding subject matter of this paragraph characterizesexample 6 of the present disclosure, wherein example 6 also includes thesubject matter according to any one of examples 1 to 5, above.

Feedstock 126 being metal or metal alloy enables additive manufacturingsystem 110 to fabricate a three-dimensional object, formed of any one ofvarious custom metals or metal alloys by depositing extrudate 112 ontosubstrate 114.

In one or more example, metal includes any one or more of a wide rangeof metals, such as, but not limited to, steel, aluminum, nickel, copper,magnesium, titanium, iron, and the like. In one or more examples, metalalloy includes any one or more of a wide range of metal alloys formed ofiron, carbon, steel, manganese, nickel, chromium, molybdenum, boron,titanium, vanadium, tungsten, cobalt, niobium, and the like orcombinations thereof.

In one or more examples, every layer of extrudate 112 deposited onsubstrate 114 is formed of the same feedstock material (e.g., the samemetal or metal alloy). In such examples, a three-dimensional object,formed by the deposition process using additive manufacturing system110, is isotropic. In one or more examples, at least one layer ofextrudate 112 deposited on substrate 114 is formed of a differentfeedstock material than at least one other layer of extrudate 112,deposited on substrate 114. In such examples, a three-dimensionalobject, formed by the deposition process using additive manufacturingsystem 110, is anisotropic.

In one or more examples, feedstock 126 is a solid material, such as asolid rod of metal or a solid rod of metal alloy.

In one or more examples, feedstock 126 is a powdered material, suchpowdered metal or powdered metal alloy.

Referring generally to FIG. 1 and particularly to, e.g., FIG. 4, diedistal end 130 axially protrudes distance D beyond tool distal end 120.The preceding subject matter of this paragraph characterizes example 7of the present disclosure, wherein example 7 also includes the subjectmatter according to any one of examples 1 to 6, above.

Die distal end 130 of die 128 protruding axially, for example, along dieaxis A_(D1) of die 128, distance D beyond tool distal end 120 locates aportion of die 128 in position to at least one of form a portion of thelayer of extrudate 112 being deposited, control a dimension of a portionof the layer of extrudate 112 being deposited, and/or control a surfacecharacteristic of a portion of the layer of extrudate 112 beingdeposited.

In one or more examples, distance D is equal to or greater than athickness dimension of the layer of extrudate 112 being deposited. Insuch examples, a portion of die 128 is suitably positioned to controlradial material flow from the deposition interface between stirring tool118 and build material and to form a side surface of the layer ofextrudate 112 being deposited.

Referring generally to FIG. 1, die 128 is formed of a first metallicmaterial, having a first composition. Stirring tool 118 is formed of asecond metallic material, having a second composition. The firstcomposition and the second composition are equivalent to each other. Thepreceding subject matter of this paragraph characterizes example 8 ofthe present disclosure, wherein example 8 also includes the subjectmatter according to any one of examples 1 to 7, above.

The first composition of the first metallic material of die 128 and thesecond composition of the second metallic material of stirring tool 118being equivalent to each other provides for die 128 and stirring tool118 having equivalent material properties and/or thermal properties.

For the purpose of the present disclosure, the term “equivalent” refersto a condition that is exactly identical to the stated condition or acondition that is substantially the same as the stated condition. Asused herein, the term “substantially” refers to a condition that issimilar to an extent that it may be perceived as being exact. Thus, thephrase “A is equivalent to B” encompasses conditions in which A isexactly the same as B, or where A is within a predetermined allowablevariance of (e.g., +/−5%) of B, or vice versa.

In one or more examples, the first composition of the first metallicmaterial of die 128 and the second composition of the second metallicmaterial of stirring tool 118 being equivalent to each other provide fordie 128 and stirring tool 118 having equivalent hardness and thermalconductivity properties. As such, additive manufacturing system 110 iscapable of sufficiently heating the interface between stirring tool 118and substrate 114 (e.g., during deposition of an initial layer ofextrudate 112) or the interface between stirring tool 118 and apreceding layer of extrudate 112 (e.g., during deposition of asubsequent layer of extrudate 112), heating the interface betweenfeedstock 126 and substrate 114 or the interface between feedstock 126and a preceding layer of extrudate 112, and/or heating the interfacebetween stirring tool 118 and feedstock 126 for deposition of extrudate112 (e.g., formation of a layer of extrudate 112) without die 128 havinga material impact on the generation, transfer, or dissipation of heatduring the deposition process.

In one or more examples, the first composition of the first metallicmaterial of die 128 and the second composition of the second metallicmaterial of stirring tool 118 is any one of various materialcompositions suitable for additive friction stir deposition. In one ormore examples, the second composition of the second metallic materialselected for stirring tool 118 is harder than the material compositionof feedstock 126 so that stirring tool 118 is not consumed during thefriction stir deposition process. In other words, stirring tool 118 is anon-consumable tool.

Similarly, in one or more examples, the first composition of the firstmetallic material selected for die 128 is harder than the materialcomposition of feedstock 126 so that die 128 is not consumed during thefriction stir deposition process. In other words, die 128 is anon-consumable tool.

In one or more examples, the first composition of the first metallicmaterial of die 128 and the second composition of the second metallicmaterial of stirring tool 118 are different. In such examples, the firstcomposition of the first metallic material of die 128 is selected for aparticular thermal effect on the generation, transfer, or dissipation ofheat during the deposition process. In one or more examples, the firstcomposition of the first metallic material of die 128 is selected tofunction as a heat sink, configured to selectively control the rate ofcooling of the layer of extrudate 112.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 4, 5, 9,and 10, die 128 is moveable relative to stirring tool 118 along die axisA_(D1) between, inclusively, at least a retracted position and anengaged position. Die distal end 130 protrudes axially outward distanceD beyond tool distal end 120 when die 128 is in the engaged position.The preceding subject matter of this paragraph characterizes example 9of the present disclosure, wherein example 9 also includes the subjectmatter according to any one of examples 1 to 8, above.

Movement of die 128 relative to stirring tool 118 between the retractedposition and the engaged position enables selective control of aflow-inhibiting function of die 128 and/or surface-forming function ofdie 128, when rotationally moving stirring tool 118 or moving depositionhead 116 during deposition of extrudate 112.

For illustrative purposes, FIGS. 4, 9, and 10 depict die 128 in theengaged position and FIG. 5 depicts die 128 in the retracted position.In one or more examples, die 128 moves along die axis A_(D1) from theretracted position to the engaged position so that die distal end 130 ofdie 128 protrudes distance D beyond tool distal end 120 of stirring tool118, as depicted in FIG. 4. When in the engaged position, die 128 issuitably located to engage a periphery (e.g., a side surface) of thelayer of extrudate 112 being deposited for performance of itsflow-inhibiting function and/or its surface-forming function. In one ormore examples, die 128 moves along die axis A_(D1) from the engagedposition to the retracted position so that die distal end 130 of die 128is approximately aligned with tool distal end 120 of stirring tool 118,as depicted in FIG. 4. When in the retracted position, die 128 issuitably located not to engage a periphery (e.g., a side surface) of thelayer of extrudate 112 being deposited.

Although the illustrative examples of the three-dimensional object,formed from layers of extrudate 112 deposited on substrate 114, depict asubstantially linear, in plan view, three-dimensional object, which isformed from substantially linear, in plan view, layers of extrudate 112,in other examples, the three-dimensional object or one or more layers ofextrudate 112 has a non-linear or complex shape, in plan view. It shouldbe appreciated that in one or more examples, the movement path ofdeposition head 116 for deposition of any given layer of extrudate 112depends on various factors, such as the geometry of a portion of thethree-dimensional object formed by the respective layers of extrudate112.

As illustrated in FIGS. 2-6, 9, and 10, in one or more examples, eachlayer of extrudate 112 is deposited by moving deposition head 116 alongan approximately linear movement path and, thus, forming a linear layerof extrudate 112. In such examples, die 128 is positioned in the engagedposition along any portion of, or an entirety of, the run of depositionhead 116 when depositing the linear layer of extrudate 112.

In one or more examples, one or more layers of extrudate 112 aredeposited by moving deposition head 116 along a non-linear movement pathand, thus, forming a non-linear layer of extrudate 112. In suchexamples, die 128 is positioned in the engaged position along anyportion of, or an entirety of, the run of deposition head 116 whendepositing the non-linear layer of extrudate 112. In one or moreexamples, die 128 is positioned in the engaged position along oneportion of the run of deposition head 116, when depositing one portionof the layer of extrudate 112, and is positioned in the retractedposition along another portion of the run of depositions head 116, whendepositing another portion of the layer of extrudate 112, such as atcorners or bends of the layer of extrudate 112 or at turns or depositionhead 116.

Referring generally to FIG. 1, additive manufacturing system 110 furthercomprises die force applicator 140, operatively connected to die 128 toselectively move die 128 along die axis A_(D1) between at least theretracted position and the engaged position. The preceding subjectmatter of this paragraph characterizes example 10 of the presentdisclosure, wherein example 10 also includes the subject matteraccording to example 9, above.

Die force applicator 140 enables selective control of a position of die128 along die axis A_(D1) relative to stirring tool 118, between theretracted position and the engaged position.

Die force applicator 140 may be any one of various types of forceapplication devices, linear motion control devices, or actuatorssuitable to selectively apply a die force to die 128 and selectivelyposition die 128 along die axis A_(D1). In one or more examples, dieforce applicator 140 is a linear actuator. In one or more examples, dieforce applicator 140 is a two-position actuator, configured to positiondie 128 in the retracted position and the engaged position. In one ormore examples, die force applicator 140 is a multi-position actuator,configured to position die 128 in the retracted position, the engagedposition, and one or more positions between the retracted position andthe engaged position.

In one or more examples, additive manufacturing system 110 includes acontrol unit communicatively coupled with die force applicator 140. Thecontrol unit is configured to provide operating instructions to dieforce applicator 140 for selective positioning of die 128 duringdeposition of extrudate 112. In an example, control unit includes aprocessor and memory and the operating instructions take the form ofcomputer readable program code, stored on the memory and executed by theprocessor.

Referring generally to FIG. 1, die force applicator 140 comprises atleast one of a pneumatic linear actuator, a hydraulic linear actuator,or a mechanical linear actuator. The preceding subject matter of thisparagraph characterizes example 11 of the present disclosure, whereinexample 11 also includes the subject matter according to example 10,above.

Use of at least one of the pneumatic linear actuator, the hydrauliclinear actuator, or the mechanical linear actuator as die forceapplicator 140 provides a simple, effective, and repeatable means ofselectively positioning die 128 along die axis A_(D1) relative tostirring tool 118, between at least the retracted position and theengaged position.

Referring generally to FIG. 1 and particularly to, e.g., FIG. 11, die128 is one of plurality of dies 328, positioned adjacent to stirringtool 118. The preceding subject matter of this paragraph characterizesexample 12 of the present disclosure, wherein example 12 also includesthe subject matter according to any one of examples 1 to 11, above.

Plurality of dies 328 serve as forming tool for controlling the geometryand/or the dimension at a plurality of sides, or of a plurality ofsurfaces, of extrudate 112 when deposited on substrate 114.

In one or more examples, plurality of dies 328 enables dimensionalcontrol of the three-dimensional object built during the depositionprocess using additive manufacturing system 110. Control of materialflow using plurality of dies 328 enables control of at least onedimension (e.g., a lateral dimension) of each layer of extrudate 112being deposited. In other words, plurality of dies 328 preventsextrudate 112 from extending beyond a desired dimension and inhibits abuild-up of excess material along a periphery (e.g., an externalboundary of a surface) of the layer of extrudate 112 being deposited.

Further, in one or more examples, plurality of dies 328 enables controlof a contour and/or control of surface characteristics of the periphery(e.g., a plurality of side surfaces) of the layer of extrudate 112 beingdeposited. In one or more examples, plurality of dies 328 provides forplanar or contoured side surfaces of the layer of extrudate 112 beingdeposited. In one or more examples, plurality of dies 328 provides forrelatively smooth side surfaces of the layer of extrudate 112 beingdeposited.

In one or more examples, plurality of dies 328 and stirring tool 118move together when depositing a layer of extrudate 112, for example, bytransverse movement of deposition head 116. In one or more examples,plurality of dies 328 and stirring tool 118 move independently. In suchexamples, at least one of plurality of dies 328 moves into position,followed by transverse movement of stirring tool 118 to deposit thelayer of extrudate 112.

In one or more examples, die force applicator 140 is operativelyconnected to each one of plurality of dies 328 to selectively move eachone of plurality of dies 328 along a respective die axis between atleast the retracted position and the engaged position.

As illustrated in FIG. 11, in one or more examples, deposition head 116includes any number of dies, such as die 128, second die 228, third die,fourth die, etc. As used herein, the term “number of” items means one ormore items. In one or more examples, each one of plurality of dies 328is positioned adjacent to stirring tool 118 and has a respective dieaxis that is parallel to the axis of rotation A_(R) of stirring tool118. In one or more examples, each one of plurality of dies 328 isindependently moveable along its respective die axis during depositionof a layer of extrudate 112.

Referring generally to FIG. 1, additive manufacturing system 110 furthercomprises stirring-tool force applicator 144, configured to urgedeposition head 116 against substrate 114. The preceding subject matterof this paragraph characterizes example 13 of the present disclosure,wherein example 13 also includes the subject matter according to any oneof examples 1 to 12, above.

Stirring-tool force applicator 144 enables selective control of aposition of stirring tool 118 relative to substrate 114 or relative to apreceding layer of extrudate 112 during deposition of extrudate 112.

Stirring-tool force applicator 144 may be any one of various types offorce application devices, linear motion control devices, or actuatorssuitable to selectively apply a stirring-tool force to stirring tool 118and selectively position stirring tool 118 relative to substrate 114 orrelative to a preceding layer of extrudate 112, such as along axis ofrotation A_(R). In one or more examples, stirring-tool force applicator144 is operatively coupled with stirring tool 118. Stirring-tool forceapplicator 144 is configured to urge stirring tool 118 against substrate114, or preceding layer of extrudate 112, such that the tool shoulder oftool proximal end 122 is in direct, physical contact with the surface ofsubstrate 114, or the surface of the preceding layer of extrudate 112,with a force sufficient to generate heat through dynamic contactfriction when stirring tool 118 rotates.

In one or more examples, stirring-tool force applicator 144 is a linearactuator. In one or more examples, stirring-tool force applicator 144includes at least one of a pneumatic linear actuator, a hydraulic linearactuator, or a mechanical linear actuator. Use of at least one of thepneumatic linear actuator, the hydraulic linear actuator, or themechanical linear actuator as stirring-tool force applicator 144provides a simple, effective, and repeatable means of selectivelypositioning stirring tool 118 relative to substrate 114.

In one or more examples, the control unit is communicatively coupledwith stirring-tool force applicator 144. The control unit is configuredto provide operating instructions to stirring-tool force applicator 144for selective positioning of stirring tool 118 during deposition ofextrudate 112.

Referring generally to FIG. 1, additive manufacturing system 110 furthercomprises stirring-tool rotation device 146, configured to rotatestirring tool 118 about axis of rotation A_(R) while stirring-tool forceapplicator 144 urges deposition head 116 against substrate 114. Thepreceding subject matter of this paragraph characterizes example 14 ofthe present disclosure, wherein example 14 also includes the subjectmatter according to example 13, above.

Stirring-tool rotation device 146 enables rapid rotation of stirringtool 118 about axis of rotation A_(R) during deposition of extrudate112.

Stirring-tool rotation device 146 may be any one of various types ofrotational force application devices, rotational motion control devices,or actuators suitable to rotate stirring tool 118 about axis of rotationA_(R). In one or more examples, stirring-tool rotation device 146 isoperatively coupled with stirring tool 118. With the tool shoulder oftool proximal end 122 of stirring tool 118 in contact with the surfaceof substrate 114 (e.g., during deposition of an initial layer ofextrudate 112) or the surface of preceding layer of extrudate 112 (e.g.,during deposition of a subsequent layer of extrudate 112), stirring-toolrotation device 146 is configured to rotate stirring tool 118 at arotational speed, sufficient to generate heat through dynamic contactfriction at the deposition interface.

In one or more examples, stirring-tool rotation device 146 is a rotaryactuator. In one or more examples, stirring-tool rotation device 146includes at least one of a pneumatic rotary actuator, a hydraulic rotaryactuator, or a mechanical rotary actuator. Use of at least one of thepneumatic rotary actuator, the hydraulic rotary actuator, or themechanical rotary actuator as stirring-tool rotation device 146 providesa simple, effective, and repeatable means of rapidly rotating stirringtool.

In one or more examples, the control unit is communicatively coupledwith stirring-tool rotation device 146. The control unit is configuredto provide operating instructions to stirring-tool rotation device 146for rotation of stirring tool 118 during deposition of extrudate 112.

Referring generally to FIG. 1, additive manufacturing system 110 furthercomprises feed-stock force applicator 148 that biases feedstock 126toward tool distal end 120. The preceding subject matter of thisparagraph characterizes example 15 of the present disclosure, whereinexample 15 also includes the subject matter according to any one ofexamples 1 to 14, above.

Feed-stock force applicator 148 urges feedstock 126 into contact withsubstrate 114 or a preceding layer of extrudate 112 during deposition ofextrudate 112.

Feed-stock force applicator 148 may be any one of various types of forceapplication devices, linear motion control devices, or actuatorssuitable to selectively apply the feed-stock force to feedstock 126 andposition feedstock 126 into contact with substrate 114 or a precedinglayer of extrudate 112, such as along axis of rotation A_(R). In one ormore examples, feed-stock force applicator 148 is operatively coupledwith feedstock 126. Feed-stock force applicator 148 is configured tourge feedstock 126 against substrate 114, or preceding layer ofextrudate 112, such that the distal end of feedstock 126, positioned at,or protruding from, tool distal end 120 of stirring tool 118 is indirect, physical contact with the surface of substrate 114 or thesurface of the preceding layer of extrudate 112 with a force, sufficientto generate heat through dynamic contact friction when feedstock 126rotates (e.g., when feedstock 126 co-rotates with stirring tool 118).

In one or more examples, feed-stock force applicator 148 is a linearactuator. In one or more examples, feed-stock force applicator 148includes at least one of a pneumatic linear actuator, a hydraulic linearactuator, or a mechanical linear actuator. Use of at least one of thepneumatic linear actuator, the hydraulic linear actuator, or themechanical linear actuator as feed-stock force applicator 148 provides asimple, effective, and repeatable means of selectively urging feedstock126 into contact with substrate 114 or a preceding layer of extrudate112.

In one or more examples, the control unit is communicatively coupledwith feed-stock force applicator 148. The control unit is configured toprovide operating instructions to feed-stock force applicator 148 forurging feedstock 126 toward tool distal end 120 of stirring tool 118(e.g., outward from bore 124) during deposition of extrudate 112.

Referring generally to FIG. 1, additive manufacturing system 110 furthercomprises carriage 150, connected to deposition head 116. Carriage 150moves deposition head 116 relative to substrate 114. The precedingsubject matter of this paragraph characterizes example 16 of the presentdisclosure, wherein example 16 also includes the subject matteraccording to any one of examples 1 to 15, above.

Carriage 150 enables deposition head 116 to move relative to substrate114 or preceding layer of extrudate 112 during deposition of asubsequent layer of extrudate 112 independent of substrate 114.

Carriage 150 may be any one or various types of motion control devicesor tool manipulators. In one or more examples, carriage 150 is aprogrammable robotic manipulator, such as a robotic arm, configured toautomatically move deposition head 116 in three-dimensional space. Insuch examples, deposition head 116 takes the form of an end effector,connected to a working end of the robotic arm.

In one or more examples, the control unit is communicatively coupledwith carriage 150. The control unit is configured to provide operatinginstructions to carriage 150 for selective positioning and moving ofdeposition head 116 during deposition of extrudate 112.

In one or more examples, additionally or alternatively, additivemanufacturing system 110 also includes second carriage 250, connected tosubstrate 114. Second carriage 250 moves substrate 114 relative todeposition head 116. Second carriage 250 enables substrate 114 to moverelative to deposition head 116 during deposition of a subsequent layerof extrudate 112 independent of deposition head 116. Second carriage 250may be any one or various types of motion control devices or toolmanipulators. In one or more examples, second carriage 250 is aprogrammable robotic manipulator, such as a robotic arm configured toautomatically move substrate 114 in three-dimensional space. In one ormore examples, the control unit is communicatively coupled with secondcarriage 250. The control unit is configured to provide operatinginstructions to second carriage 250 for selective positioning and movingof deposition head 116 during deposition of extrudate 112.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 4, 5, and7-10, die 128 comprises engagement surface 131 that defines at least oneshaping feature 133. The preceding subject matter of this paragraphcharacterizes example 17 of the present disclosure, wherein example 17also includes the subject matter according to any one of examples 1 to16, above.

Engagement surface 131 enables the flow-inhibiting function of die 128and at least one shaping feature 133 enables the surface-formingfunction of die 128.

In one or more examples, engagement surface 131 provides a physical stopthat limits a distance that plasticized build material can flow radiallyoutward from the deposition interface of stirring tool 118 duringdeposition of any layer of extrudate 112. Limiting the radial flow ofplasticized build material controls a dimension (e.g., a lateraldimension) and defines a side surface of the layer of extrudate 112being deposited. As illustrated in FIG. 4, in one or more examples,engagement surface 131 of die 128 is formed by a portion of die distalend 130 of die 128 that protrudes distance D beyond tool distal end 120of stirring tool 118.

In one or more examples, at least one shaping feature 133 provides aforming feature that controls a shape or characteristic of a sidesurface of the layer of extrudate 112 being deposited. As illustrated inFIGS. 7 and 8, in one or more examples, at least one shaping feature 133is located on, or is formed by, engagement surface 131.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 4, 5, and7, engagement surface 131 of die 128 is substantially planar. Thepreceding subject matter of this paragraph characterizes example 18 ofthe present disclosure, wherein example 18 also includes the subjectmatter according to example 17, above.

Engagement surface 131 of die 128 being substantially planar enablesformation of a correspondingly substantially planar portion of a layerof extrudate 112 being deposited.

In one or more examples, engagement surface 131 of die 128 beingsubstantially planar provides for a planar side surface of the layer ofextrudate 112 being deposited. In one or more examples, engagementsurface 131 of die 128 being substantially planar provides for arelatively smooth, flat side surface of the layer of extrudate 112 beingdeposited.

In one or more examples, engagement surface 131 of die 128 is contouredor includes a contour. Engagement surface 131 of die 128 being contouredenables formation of a correspondingly contoured portion of a layer ofextrudate 112 being deposited. In one or more examples, engagementsurface 131 of die 128 being contoured provides for a contoured sidesurface of the layer of extrudate 112 being deposited. In one or moreexamples, engagement surface 131 of die 128 being contoured provides fora relatively smooth, contoured side surface of the layer of extrudate112 being deposited.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 8 and 9,at least one shaping feature 133 comprises groove 135. The precedingsubject matter of this paragraph characterizes example 19 of the presentdisclosure, wherein example 19 also includes the subject matteraccording to example 17 or 18, above.

At least one shaping feature 133 comprising groove 135 enables formationof at least one surface feature 220 (FIG. 9) during deposition of alayer of extrudate 112.

In one or more examples, groove 135 provides for formation of acorresponding, complementary ridge, e.g., surface feature 220, (FIG. 9)located on, or protruding from, a side surface of the layer of extrudate112 being deposited. As illustrated in FIGS. 8 and 9, in one or moreexamples, at least one shaping feature 133 includes a plurality ofgrooves that provide for formation of a corresponding plurality ofridges and grooves (e.g., at least one surface feature 220) on the sidesurface of the layer of extrudate 112 being deposited.

In one or more other examples, at least one shaping feature 133 includesany one of various other geometric shaping features configured to format least one surface feature 220, complementary thereto, on the layer ofextrudate 112 being deposited having any one of various geometries.

Referring generally to FIG. 1 and particularly to, e.g., FIG. 10, die128 is rotatable about die axis A_(D1). The preceding subject matter ofthis paragraph characterizes example 20 of the present disclosure,wherein example 20 also includes the subject matter according to any oneof examples 1 to 17, above.

Rotational movement of die 128 about die axis A_(D1) enables die 128 toassist in formation of any layer of extrudate 112 during deposition.

In one or more examples, during the additive friction stir depositionprocess using additive manufacturing system 110, die 128 rapidly rotatesto generate heat through dynamic contact friction between die 128 (e.g.,engagement surface 131 of die 128) and a portion of the layer ofextrudate 112 being deposited. In one or more examples, generation ofheat proximate to the periphery of the layer of extrudate 112 beingdeposited improves the quality of the three-dimensional object builtusing additive manufacturing system 110.

In one or more examples, during the additive friction stir depositionprocess using additive manufacturing system 110, die 128 rotates tosmooth or otherwise shape at least a portion of the periphery (e.g.,side surface) of the layer of extrudate 112 being deposited.

In one or more examples, die 128 has an approximately cylindrical shape,or an approximately circular shape in cross-section, viewed along dieaxis A_(D1).

Referring generally to FIG. 1, additive manufacturing system 110 furthercomprises die-rotation device 142, operatively connected to die 128 torotate die 128 about die axis A_(D1). The preceding subject matter ofthis paragraph characterizes example 21 of the present disclosure,wherein example 21 also includes the subject matter according to example20, above.

Die-rotation device 142 enables rotation of die 128 about die axisA_(D1) during deposition of extrudate 112.

Die-rotation device 142 may be any one of various types of rotationalforce application devices, rotational motion control devices, oractuators suitable to rotate die 128 about die axis A_(D1). In one ormore examples, die-rotation device 142 is operatively coupled with die128. With engagement surface 131 of die 128 in contact with the surfaceof a layer of extrudate being deposited, die-rotation device 142 isconfigured to rotate die 128. In one or more examples, die-rotationdevice 142 is configured to rotate die 128 at a rotational speed,sufficient to generate heat through dynamic contact friction. In one ormore examples, die-rotation device 142 is configured to rotate die 128at a rotational speed, sufficient to smooth or otherwise form a sidesurface of the layer of extrudate 112 being deposited.

Referring generally to FIG. 1 and particularly to, e.g., FIGS. 3-6 and9-11, additive manufacturing system 110 further comprises second die228. Second die 228 is positioned adjacent to stirring tool 118, definessecond-die axis A_(D2), and comprises second-die distal end 230 andsecond-die proximal end 232, axially opposing second-die distal end 230along second-die axis A_(D2). Second-die axis A_(D2) is parallel withaxis of rotation A_(R) of stirring tool 118. The preceding subjectmatter of this paragraph characterizes example 22 of the presentdisclosure, wherein example 22 also includes the subject matteraccording to example 20 or 21, above.

Second die 228 serves as a forming tool for controlling geometry and/ordimensions of a second side, or second surface, of extrudate 112 whendeposited on substrate 114.

In one or more example, second die 228 is one of plurality of dies 328(FIG. 10).

In one or more examples, surface quality of at least one layer of, oreach layer of, extrudate 112 and, thus, surface quality of at least aportion of the three-dimensional object, or the three-dimensional objectas a whole, is improved by use of second die 228. As illustrated inFIGS. 3-6 and 9-11, in one or more examples, second die 228 is located,or is positioned, adjacent to stirring tool 118 during deposition ofextrudate 112, such as laterally opposite to die 128. It should beappreciated that the location of second die 228 relative to stirringtool 118 (e.g., the degree of proximity of second die 228 relative tostirring tool 118) depends on various factors, including, but notlimited to, the desired (e.g., lateral) dimension of the layer ofextrudate 112 being deposited along any given run of deposition head 116or the desired (e.g., lateral) dimensions of the three-dimensionalobject.

In one or more examples, second-die axis A_(D2) of second die 228 andaxis of rotation A_(R) of stirring tool 118 are parallel to each otherand reside in the same virtual plane. In one or more examples,second-die axis A_(D2) of second die 228 and die axis A_(D1) of die 128are parallel to each other and reside in the same virtual plane. In oneor more examples, second-die axis A_(D2) of second die 228 resides in avirtual second die-plane and axis of rotation A_(R) of stirring tool 118resides in a virtual tool-plane, and the virtual die-plane and thevirtual tool-plane are parallel to each other. In one or more examples,second-die axis A_(D2) of second die 228 resides in a virtual seconddie-plane and die axis A_(D1) of die 128 resides in a virtual die-plane,and the virtual second die-plane and the virtual die-plane are parallelto each other.

Generally, during the deposition process, a portion of plasticized buildmaterial (e.g., softened portions of a current layer of extrudate 112being deposited and a previous layer of extrudate 112 on which thecurrent layer of extrudate 112 is deposited or substrate 114 on whichthe current layer of extrudate 112 is deposited) flows radially outwardfrom a deposition interface (e.g., the interface between stirring tool118 and the build material). Second die 228 is suitably located relativeto stirring tool 118, or relative to the deposition interface betweenstirring tool 118 and the build material, so that second die 228controls a material flow of plasticized build material that radiatesoutward from the deposition interface. In other words, second die 228serves as a physical stop for a radial flow of plasticized buildmaterial.

In one or more examples, second die 228 enables dimensional control ofthe three-dimensional object built during the deposition process usingadditive manufacturing system 110, for example, laterally opposite die128. Control of material flow using second die 228 enables control of atleast one dimension (e.g., a lateral dimension) of each layer ofextrudate 112 being deposited. In other words, second die 228 preventsextrudate 112 from extending beyond a desired dimension and inhibits abuild-up of excess material along a periphery (e.g., an externalboundary of a surface) of the layer of extrudate 112 being deposited.

Further, in one or more examples, second die 228 enables control of acontour and/or control of surface characteristics of the periphery(e.g., side surface) of the layer of extrudate 112 being deposited, forexample, laterally opposite die 128. In one or more examples, second die228 provides for a planar or contoured side surface of the layer ofextrudate 112 being deposited. In one or more examples, second die 228provides for a relatively smooth side surface of the layer of extrudate112 being deposited.

In one or more examples, second die 228, die 128, and stirring tool 118move together when depositing a layer of extrudate 112, for example, bytransverse movement of deposition head 116. In one or more examples,second die 228, die 128, and stirring tool 118 move independently. Insuch examples, second die 228 and die 128 moves into position, followedby transverse movement of stirring tool 118 to deposit the layer ofextrudate 112.

As illustrated in FIGS. 4 and 5, in one or more examples, secondshortest distance 236 between die 128 and outer surface 134 is at most 3millimeters. In one or more examples, shortest distance 136 between die128 and outer surface 134 is at most 1 millimeter. It should beappreciated that shortest distance 136 between second die 228 and outersurface 134 of stirring tool 118 depends on various factors, including,but not limited to, the desired (e.g., lateral) dimension of the layerof extrudate 112 being deposited along any given run of deposition head116 or the desired (e.g., lateral) dimensions of the three-dimensionalobject.

As illustrated in FIGS. 4, 5, 9, and 10, in one or more examples,second-die distal end 230 axially protrudes distance D₂ beyond tooldistal end 120. Second-die distal end 230 of second die 228 protrudingaxially, for example, along second-die axis A_(D2) of second die 228,distance D₂ beyond tool distal end 120 locates a portion of second die228 in position to at least one of form a portion of the layer ofextrudate 112 being deposited, control a dimension of a portion of thelayer of extrudate 112 being deposited, and/or control a surfacecharacteristic of a portion of the layer of extrudate 112 beingdeposited

In one or more examples, distance D₂ is equal to or greater than athickness dimension of the layer of extrudate 112 being deposited. Insuch examples, a portion of second die 228 is suitably positioned tocontrol radial material flow from the deposition interface betweenstirring tool 118 and build material and to form a side surface of thelayer of extrudate 112 being deposited.

In one or more example, distance D of die 128 and distance D₂ of seconddie 228 are equivalent during deposition of any given layer of extrudate112. In one or more example, distance D of die 128 and distance D₂ ofsecond die 228 are different during deposition of any given layer ofextrudate 112.

In one or more examples, second die 228 is formed of a third metallicmaterial, having a third composition. In one or more examples, the thirdcomposition of the third metallic material of second die 228 and thesecond composition of the second metallic material of stirring tool 118are equivalent to each other. In one or more examples, the thirdcomposition of the third metallic material of second die 228 and thefirst composition of the first metallic material of die 128 areequivalent to each other.

Generally, in one or more examples, the third composition of the thirdmetallic material selected for second die 228 is harder than thematerial composition of feedstock 126 so that second die 228 is notconsumed during the friction stir deposition process. In other words,second die 228 is a non-consumable tool.

As illustrated in FIGS. 4, 5, 9, and 10, in one or more examples, seconddie 228 is moveable relative to stirring tool 118 along second-die axisA_(D2) between, inclusively, at least a retracted position and anengaged position. Second-die distal end 230 protrudes axially outwarddistance D₂ beyond tool distal end 120 when second die 228 is in theengaged position. Movement of second die 228 relative to stirring tool118 between the retracted position and the engaged position enablesselective control of a flow-inhibiting function of second die 228 and/orsurface-forming function of second die 228 when rotationally movingstirring tool 118 or moving deposition head 116 during deposition ofextrudate 112.

For illustrative purposes, FIGS. 4, 5, 9, and 10 depict second die 228in the engaged position and FIG. 5 depicts second die 228 in theretracted position (shown by broken lines). In one or more examples,second die 228 moves along second-die axis A_(D2) from the retractedposition to the engaged position so that second-die distal end 230 ofsecond die 228 protrudes distance D₂ beyond tool distal end 120 ofstirring tool 118, as depicted in FIG. 5. When in the engaged position,second die 228 is suitably located to engage a periphery (e.g., a sidesurface) of the layer of extrudate 112 being deposited for performanceof its flow-inhibiting function and/or its surface-forming function. Inone or more examples, second die 228 moves along second-die axis A_(D2)from the engaged position to the retracted position so that second-diedistal end 230 of second die 228 is approximately aligned with tooldistal end 120 of stirring tool 118. When in the retracted position,second die 228 is suitably located not to engage a periphery (e.g., aside surface) of the layer of extrudate 112 being deposited.

In one or more examples, die force applicator 140 (FIG. 1) isoperatively connected to second die 228 to selectively move second die228 along second-die axis A_(D2) between at least the retracted positionand the engaged position.

As illustrated in FIGS. 7-9, in one or more examples, second die 228includes second engagement surface 231 that defines at least one secondshaping feature, such as at least one shaping feature 133, illustratedin FIG. 8.

Referring generally to FIG. 1 and particularly to, e.g., FIG. 10, seconddie 228 is rotatable about second-die axis A_(D2). The preceding subjectmatter of this paragraph characterizes example 23 of the presentdisclosure, wherein example 23 also includes the subject matteraccording to example 22, above.

Rotating second die 228 about die axis A_(D2) enables second die 228 toassist in formation of any layer of extrudate 112 during deposition.

In one or more examples, during the additive friction stir depositionprocess using additive manufacturing system 110, second die 228 rapidlyrotates to generate heat through dynamic contact friction between seconddie 228 (e.g., second engagement surface 231 of second die 228) and aportion of the layer of extrudate 112 being deposited. In one or moreexamples, generation of heat proximate to the periphery of the layer ofextrudate 112 being deposited improves the quality of thethree-dimensional object built using additive manufacturing system 110.

In one or more examples, during the additive friction stir depositionprocess using additive manufacturing system 110, second die 228 rotatesto smooth or otherwise shape at least a portion of the periphery (e.g.,side surface) of the layer of extrudate 112 being deposited.

In one or more examples, second die 128 has an approximately cylindricalshape, or an approximately circular shape in cross-section, viewed alongdie axis A_(D2).

In one or more examples, die-rotation device 142 (FIG. 1) is operativelyconnected to second die 228 to rotate second die 228 about second-dieaxis A_(D2).

Referring generally to FIG. 1 and particularly to, e.g., FIG. 10, die128 is rotatable in first direction R₁ about die axis A_(D1), and seconddie 228 is rotatable in second direction R₂ about second-die axisA_(D2). First direction R₁ and second direction R₂ are opposite to eachother. The preceding subject matter of this paragraph characterizesexample 24 of the present disclosure, wherein example 24 also includesthe subject matter according to example 23, above.

Rotation of die 128 in first direction R₁ and rotation of second die 228in second direction R₂ that is opposite to first direction R₁ mitigates,or offsets, the effect of torque applied to deposition head 116 or pullon deposition head 116 due to frictional contact between die 128 and/orsecond die 228 and extrudate 112 during respective rotation of die 128and/or second die 228.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1-11,method 1000 of depositing extrudate 112 onto substrate 114 is disclosed.Method comprises (Block 1002) rotating stirring tool 118 about axis ofrotation A_(R) while urging tool distal end 120 of stirring tool 118against substrate 114. Stirring tool 118 defines bore 124, extendingtherethrough. Method 1000 further comprises (Block 1004) positioning die128 adjacent to stirring tool 118, such that stirring tool 118 rotatesrelative to die 128. Method 1000 also comprises (Block 1006) passingfeedstock 126 through bore 124 toward tool distal end 120. The precedingsubject matter of this paragraph characterizes example 25 of the presentdisclosure.

Method 1000 facilitates depositing layers of extrudate 112 ontosubstrate 114 to form a three-dimensional object. Die 128 provides atleast one of a flow-inhibiting function and a surface-forming functionfor controlling geometry and/or dimensions of a side, or a surface, ofextrudate 112 when depositing extrudate 112 on substrate 114.

According to method 1000, in one or more examples, feedstock 126 isdelivered through bore 124 of stirring tool 118. The step of (Block1002) rapidly rotating stirring tool 118 generates heat through dynamiccontact friction at a tool-material interface. Heat is generated bydynamic contact friction between stirring tool 118 and build material.Heat is dissipated by plastic deformation of the build material. Heat istransferred inside the build material by thermal conduction and thermalconvection via material flow.

As illustrated in FIGS. 2, 3, and 6, transverse motion of stirring tool118, for example, in the direction of directional arrow 200, results indeposition of a single track, or a single layer, of extrudate 112. Asbest illustrated in FIGS. 4, 5, 9, and 10, a three-dimensional object ismade by selectively adding subsequent layers of extrudate 112 uponpreceding layers of extrudate 112 (e.g., three layers of extrudate 112are depicted in FIGS. 4, 5, 9, and 10).

In one or more examples, surface quality of at least one layer of, oreach layer of, extrudate 112 and, thus, surface quality of at least aportion of the three-dimensional object, or the three-dimensional objectas a whole, is improved by use of die 128. According to method 1000,during the deposition process, a portion of plasticized build material(e.g., softened portions of a current layer of extrudate 112 beingdeposited and a previous layer of extrudate 112 on which the currentlayer of extrudate 112 is deposited or substrate 114 on which thecurrent layer of extrudate 112 is deposited) flows radially outward froma deposition interface (e.g., the interface between stirring tool 118and the build material). The step of (Block 1004) positioning die 128relative to stirring tool 118, or relative to the deposition interfacebetween stirring tool 118 and the build material, controls a materialflow of plasticized build material that radiates outward from thedeposition interface. In other words, die 128 serves as a physical stopfor a radial flow of plasticized build material

In one or more examples, die 128 and stirring tool 118 move togetherwhen depositing a layer of extrudate 112, for example, by transversemovement of deposition head 116. In one or more examples, die 128 andstirring tool 118 move independently. In such examples, die 128 movesinto position, followed by transverse movement of stirring tool 118 todeposit the layer of extrudate 112.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1-6, 9,and 10, according to method 1000, feedstock 126 forms extrudate 112 uponexiting tool distal end 120. The preceding subject matter of thisparagraph characterizes example 26 of the present disclosure, whereinexample 26 also includes the subject matter according to example 25,above.

Heated and softened, feedstock 126 is fed through bore 124 of stirringtool 118 and exits tool distal end 120 of stirring tool 118 as extrudate112 and bonds with substrate 114, or preceding layer of extrudate 112,through plastic deformation at the deposition interface.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1-6, 9,and 10, according to method 1000, die 128 is positioned to inhibitmovement of extrudate 112 radially outward, relative to axis of rotationA_(R). The preceding subject matter of this paragraph characterizesexample 27 of the present disclosure, wherein example 27 also includesthe subject matter according to example 26, above.

Positioning die 128 radially outward relative to axis of rotation A_(R)of stirring tool 118 enables selective control of a flow-inhibitingfunction of die 128 and/or surface-forming function of die 128 whenrotationally moving stirring tool 118 or moving deposition head 116during deposition of extrudate 112.

According to method 1000, in one or more examples, (Block 1004)positioning die 128 and (Block 1010) moving die 128 into the engagedposition enables dimensional control of the three-dimensional objectbuilt during the deposition process using additive manufacturing system110. Control of material flow using die 128 enables control of at leastone dimension (e.g., a lateral dimension) of each layer of extrudate 112being deposited. In other words, die 128 prevents extrudate 112 fromextending beyond a desired dimension and inhibits a build-up of excessmaterial along a periphery (e.g., an external boundary of a surface) ofthe layer of extrudate 112 being deposited.

According to method 1000, in one or more examples, (Block 1004)positioning die 128 and (Block 1010) moving die 128 into the engagedposition also enables control of a contour and/or control of surfacecharacteristics of the periphery (e.g., side surface) of the layer ofextrudate 112 being deposited. In one or more examples, die 128 providesfor a planar or contoured side surface of the layer of extrudate 112being deposited. In one or more examples, die 128 provides for arelatively smooth side surface of the layer of extrudate 112 beingdeposited.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1 and 4,according to method 1000, (Block 1004) positioning die 128 adjacent tostirring tool 118 comprises (Block 1008) positioning die 128 such thatdie distal end 130 of die 128 protrudes axially outward distance Dbeyond tool distal end 120. The preceding subject matter of thisparagraph characterizes example 28 of the present disclosure, whereinexample 28 also includes the subject matter according to any one ofexamples 25 to 27, above.

Positioning die 128 so that die distal end 130 of die 128 protrudesaxially, for example, along die axis A_(D1) of die 128, distance Dbeyond tool distal end 120 suitably locates a portion of die 128 inposition to at least one of form a portion of the layer of extrudate 112being deposited, control a dimension of a portion of the layer ofextrudate 112 being deposited, and/or control a surface characteristicof a portion of the layer of extrudate 112 being deposited.

In one or more examples, distance D is equal to or greater than athickness dimension of the layer of extrudate 112 being deposited. Insuch examples, a portion of die 128 is suitably positioned to controlradial material flow from the deposition interface between stirring tool118 and build material and to form a side surface of the layer ofextrudate 112 being deposited.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1, 4, 5,9, and 10, according to method 1000, die 128 is moveable relative tostirring tool 118 along die axis A_(D1) between at least the retractedposition and the engaged position. Method 1000 further comprises (Block1010) moving die 128 along die axis A_(D1) to the engaged position priorto (Block 1006) passing feedstock 126 through bore 124 toward tooldistal end 120. The preceding subject matter of this paragraphcharacterizes example 29 of the present disclosure, wherein example 29also includes the subject matter according to any one of examples 25 to28, above.

Moving die 128 relative to stirring tool 118 between the retractedposition and the engaged position enables selective control of aflow-inhibiting function of die 128 and/or surface-forming function ofdie 128 when rotationally moving stirring tool 118 or moving depositionhead 116 during deposition of extrudate 112.

Referring generally to FIG. 12 and particularly to, e.g., FIG. 1,according to method 1000, (Block 1010) moving die 128 along die axisA_(D1) to engaged position comprises (Block 1012) actuating at least oneof a pneumatic linear actuator, a hydraulic linear actuator, or amechanical linear actuator. The preceding subject matter of thisparagraph characterizes example 30 of the present disclosure, whereinexample 30 also includes the subject matter according to example 29,above.

Actuating at least one of the pneumatic linear actuator, the hydrauliclinear actuator, or the mechanical linear actuator provides a simple,effective, and repeatable means of selectively positioning die 128 alongdie axis A_(D1) relative to stirring tool 118, between at least theretracted position and the engaged position.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1 and10, method 1000 further comprises (Block 1014) rotating die 128 aboutdie axis A_(D1). The preceding subject matter of this paragraphcharacterizes example 31 of the present disclosure, wherein example 31also includes the subject matter according to any one of examples 25 to30, above.

Rotating die 128 about die axis A_(D1) enables die 128 to assist information of any layer of extrudate 112 during deposition.

According to method 1000, in one or more examples, (Block 1014) rotatingdie 128 generates heat through dynamic contact friction between die 128(e.g., engagement surface 131 of die 128) and a portion of the layer ofextrudate 112 being deposited. In one or more examples, generation ofheat proximate to the periphery of the layer of extrudate 112 beingdeposited improves the quality of the three-dimensional object builtusing additive manufacturing system 110.

According to method 1000, in one or more examples, (Block 1014) rotatingdie 128 shape at least a portion of the periphery (e.g., side surface)of the layer of extrudate 112 being deposited.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1-6 and9-11, method 1000 further comprises (Block 1016) positioning second die228 adjacent to stirring tool 118, such that stirring tool 118 rotatesrelative to second die 228. The preceding subject matter of thisparagraph characterizes example 32 of the present disclosure, whereinexample 32 also includes the subject matter according to example 31,above.

Positioning second die 228 provides at least one of a flow-inhibitingfunction and a surface-forming function for controlling geometry and/ordimensions of a second side, or second surface, of extrudate 112 whendepositing extrudate 112 on substrate 114.

According to method 1000, in one or more example, (Block 1016)positioning second die 228 positions second die 228 radially outwardrelative to axis of rotation A_(R) of stirring tool 118 and enablesselective control of a flow-inhibiting function of second die 228 and/orsurface-forming function of second die 228 when rotationally movingstirring tool 118 or moving deposition head 116 during deposition ofextrudate 112. In one or more examples, (Block 1016) positioning seconddie 228 positions second die 228 so that second-die distal end 230 ofsecond die 228 protrudes axially, for example, along second-die axisA_(D2) of second die 228, distance D₂ beyond tool distal end 120suitably locates a portion of second die 228 in position to at least oneof form a portion of the layer of extrudate 112 being deposited, controla dimension of a portion of the layer of extrudate 112 being deposited,and/or control a surface characteristic of a portion of the layer ofextrudate 112 being deposited.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1 and10, method 1000 further comprises (Block 1018) rotating second die 228about second-die axis A_(D2). The preceding subject matter of thisparagraph characterizes example 33 of the present disclosure, whereinexample 33 also includes the subject matter according to example 32,above.

Rotating second die 228 about second-die axis A_(D2) enables second die228 to assist in formation of any layer of extrudate 112 duringdeposition.

According to method 1000, in one or more examples, (Block 1018) rotatingsecond die 228 generates heat through dynamic contact friction betweensecond die 228 (e.g., second engagement surface 231 of second die 228)and a portion of the layer of extrudate 112 being deposited. In one ormore examples, generation of heat proximate to the periphery of thelayer of extrudate 112 being deposited improves the quality of thethree-dimensional object built using additive manufacturing system 110.

According to method 1000, in one or more examples, (Block 1018) rotatingsecond die 228 shapes at least a portion of the periphery (e.g., sidesurface) of the layer of extrudate 112 being deposited.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1 and10, according to method 1000, (Block 1018) rotating second die 228 aboutsecond-die axis A_(D2) comprises (Block 1020) rotating second die 228 insecond direction R₂ about second-die axis A_(D2), while die 128 rotatesin first direction R₁ about die axis A_(D1). Second direction R₂ andfirst direction R₁ are opposite to each other. The preceding subjectmatter of this paragraph characterizes example 34 of the presentdisclosure, wherein example 34 also includes the subject matteraccording to example 33, above.

Rotating die 128 in first direction R₁ and rotating second die 228 insecond direction R₂ that is opposite to first direction R₁ mitigates, oroffsets, the effect of torque applied to deposition head 116 or pull ondeposition head 116 due to frictional contact between die 128 and/orsecond die 228 and extrudate 112 during respective rotation of die 128and/or second die 228.

Referring generally to FIG. 12 and particularly to, e.g., FIGS. 1-3 and6, method 1000 further comprises (Block 1022) causing axis of rotationA_(R) of stirring tool 118 to move relative to substrate 114. Thepreceding subject matter of this paragraph characterizes example 35 ofthe present disclosure, wherein example 35 also includes the subjectmatter according to any one of examples 25 to 34, above.

Moving axis of rotation A_(R) of stirring tool 118 relative to substrate114, for example, in the direction of directional arrow 200, results indeposition of a track, or a layer, of extrudate 112.

Referring generally to FIG. 12 and particularly to, e.g., FIG. 1,aircraft component, manufactured according to method 1000 is disclosed.The preceding subject matter of this paragraph characterizes example 36of the present disclosure, wherein example 36 also includes the subjectmatter according to any one of examples 25 to 35, above.

Aircraft component is an example of a three-dimensional objectadditively manufactured according to method 1000 an using additivemanufacturing system 100.

Examples of the present disclosure may be described in the context ofaircraft manufacturing and service method 1100 as shown in FIG. 13 andaircraft 1102 as shown in FIG. 14. During pre-production, illustrativemethod 1100 may include specification and design (block 1104) ofaircraft 1102 and material procurement (Block 1106). During production,component and subassembly manufacturing (Block 1108) and systemintegration (Block 1110) of aircraft 1102 may take place. Thereafter,aircraft 1102 may go through certification and delivery (Block 1112) tobe placed in service (Block 1114). While in service, aircraft 1102 maybe scheduled for routine maintenance and service (Block 1116). Routinemaintenance and service may include modification, reconfiguration,refurbishment, etc. of one or more systems of aircraft 1102.

Each of the processes of illustrative method 1100 may be performed orcarried out by a system integrator, a third party, and/or an operator(e.g., a customer). For the purposes of this description, a systemintegrator may include, without limitation, any number of aircraftmanufacturers and major-system subcontractors; a third party mayinclude, without limitation, any number of vendors, subcontractors, andsuppliers; and an operator may be an airline, leasing company, militaryentity, service organization, and so on.

As shown in FIG. 14, aircraft 1102 produced by illustrative method 1100may include airframe 1118 with a plurality of high-level systems 1120and interior 1122. Examples of high-level systems 1120 include one ormore of propulsion system 1124, electrical system 1126, hydraulic system1128, and environmental system 1130. Any number of other systems may beincluded. Although an aerospace example is shown, the principlesdisclosed herein may be applied to other industries, such as theautomotive industry. Accordingly, in addition to aircraft 1102, theprinciples disclosed herein may apply to other vehicles, e.g., landvehicles, marine vehicles, space vehicles, etc.

Apparatus(es) and method(s) shown or described herein may be employedduring any one or more of the stages of the manufacturing and servicemethod 1100. For example, components or subassemblies corresponding tocomponent and subassembly manufacturing (block 1108) may be fabricatedor manufactured in a manner similar to components or subassembliesproduced while aircraft 1102 is in service (Block 1114). Also, one ormore examples of the apparatus(es), method(s), or combination thereofmay be utilized during production stages (Blocks 1108 and 1110), forexample, by substantially expediting assembly of or reducing the cost ofaircraft 1102. Similarly, one or more examples of the apparatus ormethod realizations, or a combination thereof, may be utilized, forexample and without limitation, while aircraft 1102 is in service (Block1114) and/or during maintenance and service (Block 1116).

Different examples of the apparatus(es) and method(s) disclosed hereininclude a variety of components, features, and functionalities. Itshould be understood that the various examples of the apparatus(es) andmethod(s) disclosed herein may include any of the components, features,and functionalities of any of the other examples of the apparatus(es)and method(s) disclosed herein in any combination, and all of suchpossibilities are intended to be within the scope of the presentdisclosure.

Many modifications of examples set forth herein will come to mind to oneskilled in the art to which the present disclosure pertains having thebenefit of the teachings presented in the foregoing descriptions and theassociated drawings.

Therefore, it is to be understood that the present disclosure is not tobe limited to the specific examples illustrated and that modificationsand other examples are intended to be included within the scope of theappended claims. Moreover, although the foregoing description and theassociated drawings describe examples of the present disclosure in thecontext of certain illustrative combinations of elements and/orfunctions, it should be appreciated that different combinations ofelements and/or functions may be provided by alternative implementationswithout departing from the scope of the appended claims. Accordingly,parenthetical reference numerals in the appended claims are presentedfor illustrative purposes only and are not intended to limit the scopeof the claimed subject matter to the specific examples provided in thepresent disclosure.

What is claimed is:
 1. A method (1000) of depositing an extrudate (112)onto a substrate (114), the method comprising steps of: rotating astirring tool (118) about an axis of rotation (A_(R)) while urging atool distal end (120) of the stirring tool (118) against the substrate(114), and wherein the stirring tool (118) defines a bore (124),extending therethrough; positioning a die (128) adjacent to the stirringtool (118), such that the stirring tool (118) rotates relative to thedie (128); and passing feedstock (126) through the bore (124) toward thetool distal end (120).
 2. The method according to claim 1, wherein thefeedstock (126) forms the extrudate (112) upon exiting the tool distalend (120).
 3. The method (1000) according to claim 2, wherein the die(128) is positioned to inhibit movement of the extrudate (112) radiallyoutward, relative to the axis of rotation (A_(R)).
 4. The method (1000)according to claim 1, wherein the step of positioning the die (128)adjacent to the stirring tool (118) comprises positioning the die (128)such that a die distal end (130) of the die (128) protrudes axiallyoutward a distance (D) beyond the tool distal end (120).
 5. The method(1000) according to claim 1, wherein the die (128) is moveable relativeto the stirring tool (118) along a die axis (A_(D1)) between at least aretracted position and an engaged position.
 6. The method (1000)according to claim 5, further comprising a step of moving the die (128)along the die axis (A_(D1)) to the engaged position prior to the step ofpassing the feedstock (126) through the bore (124) toward the tooldistal end (120).
 7. The method (1000) according to claim 6, wherein thestep of moving the die (128) along the die axis (A_(D1)) to the engagedposition comprises actuating a pneumatic linear actuator.
 8. The method(1000) according to claim 6, wherein the step of moving the die (128)along the die axis (A_(D1)) to the engaged position comprises actuatinga hydraulic linear actuator.
 9. The method (1000) according to claim 6,wherein the step of moving the die (128) along the die axis (A_(D1)) tothe engaged position comprises actuating a mechanical linear actuator.10. The method (1000) according to claim 1, further comprising rotatingthe die (128) about a die axis (A_(D1)).
 11. The method (1000) accordingto claim 10, further comprising positioning a second die (228) adjacentto the stirring tool (118), such that the stirring tool (118) rotatesrelative to the second die (228).
 12. The method (1000) according toclaim 11, further comprising a step of rotating the second die (228)about a second-die axis (A_(D2)).
 13. The method (1000) according toclaim 12, wherein the step of rotating the second die (228) about thesecond-die axis (A_(D2)) comprises rotating the second die (228) in asecond direction R₂ about the second-die axis (A_(D2)), while the die(128) rotates in a first direction (R₁) about the die axis (A_(D1)). 14.The method (1000) according to claim 13, wherein the second direction(R₂) and the first direction (R₁) are opposite to each other.
 15. Themethod (1000) according to claim 1, further comprising causing the axisof rotation (A_(R)) of the stirring tool (118) to move relative to thesubstrate (114).
 16. The method (1000) according to claim 1, wherein:the stirring tool (118) comprises an outer surface (134), and a shortestdistance (136) between the die (128) and the outer surface (134) is atmost three millimeters.
 17. The method (1000) according to claim 1,wherein: the stirring tool (118) comprises an outer surface (134), and ashortest distance (136) between the die (128) and the outer surface(134) is at most one millimeter.
 18. The method (1000) according toclaim 1, wherein the feedstock (126) is received in the bore (124) suchthat rotation of the stirring tool (118) causes corresponding rotationof the feedstock (126).
 19. The method (1000) according to claim 1,wherein the feedstock (126) comprises a metal or a metal alloy.
 20. Anaircraft component, manufactured according to the method (1000) of claim1.